Sediment and rocks carried by the river rub against the banks and bed of the river, it erodes.

4 of 10

Attrition

Rocks in the river smash and rub against each other, smoothing the rocks.

5 of 10

Solution

The water dissolves the particles, creating a solution.

6 of 10

Suspension

Fine particles are suspended and carried through the river.

7 of 10

Saltation

Small rocks and pebbles are bounced along the river bed.

8 of 10

Traction

Large boulders and rocks are rolled along the bed.

9 of 10

Lower course

As the river approaches the mouth, velocity and energy increase due to increased discharge. The river performs more lateral erosion making the channel wider, and smoother. As a result there is less turbulence and friction, water flow more efficient.